Abstract
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genes have been shown to be critically required for the development of specific tissues and organs during embryogenesis. In addition,
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genes are expressed in a handful of adult tissues where they are thought to play important roles, usually different from those in embryogenesis. A common theme in adult tissues is a requirement for
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gene expression in adult stem cell maintenance or tissue regeneration. The connections between adult stem cell
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gene expression and cancer are intriguing, and the literature is replete with examples of
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gene expression in either situation. Here we systematically review the literature and present an overview of postnatal
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gene expression in normal and cancerous tissue. We discuss the potential link between
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gene expression in adult tissue and cancer. In addition, we discuss whether persistent
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gene expression in cancer is favorable or unfavorable.